Service and Parts Manual (2019, 2020, 2021, 2022)

23 PB
OPERATION
Fan Only Mode Operation
During the appliance run in this mode; the compressor and outdoor fan stop and the indoor fan operates under the pre-
setting of air volume. The louver swing and the indoor fan speed is the same as the Heating Mode.
Defrost
Conditions for Defrost Activation:
The following three conditions must be met to activate Defrost.
• Condition 1: Outdoor ambient sensor is below 28.4F
• Condition 2: When the heating compressor consecutively runs for 40 minutes .
• Condition 3: The difference between the condenser coil pipe sensor outdoor ambient temperature sensor ≥10F.
Defrosting actions:
• The compressor stops, and the outdoor fan stops after delay of 30 seconds; in 50 seconds the four-way valve is powered
off; and in 10 seconds the compressor starts and runs at “defrosting frequency”.
Conditions for ending defrosting:
Defrosting is over if either of the conditions below are met.
• Condition 1: The accumulated time of defrosting is longer than 12 minutes (EEPROM setting value in the current
operating mode).
• Condition 2: If the temperature of coiled pipe is equal to or higher than 57°F (EEPROM setting value in the current
operating mode).
Actions of exiting the defrosting state:
• The compressor stops. 50 seconds later the four-way valve opens, and another 10 seconds later the compressor and
outdoor fan restart and begin normal operation.
Conditions of anti-freezing prohibition of frequency rising:
• Condition 1: in the case of anti-freezing frequency decreasing, the temperature of indoor heat exchanger rises to “anti-
freezing frequency decreasing temperature”.
• Condition 2: in normal operation, the temperature of indoor heat exchanger reaches “anti-freezing prohibition of
frequency rising temperature”.
• If either of the above two conditions is met, the product will enter anti-freezing prohibition of frequency rising state.
• Anti-freezing prohibition of frequency rising operation: the compressor is kept at the current frequency, which may
decrease according to situations while cannot rise. The outdoor fan runs.
Condition for the end of anti-freezing prohibition of frequency rising state:
• When the temperature of indoor heat exchanger rises to “anti-freezing releasing temperature”, the state of anti-
freezing prohibition of frequency rising is released.